Stowage/go
2
0
Fork 0
mirror of https://github.com/golang/go.git synced 2025-12-08 06:10:04 +00:00
Code Issues Projects Releases Packages Wiki Activity

Add and AddByte

Browse source 
R=rsc
DELTA=83  (83 added, 0 deleted, 0 changed)
OCL=34584
CL=34584
This commit is contained in:
Rob Pike 2009-09-13 21:35:18 -07:00
parent 61dd8363ba
commit d3013d8aa1
2 changed files with 83 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

42
src/pkg/bytes/bytes.go
View file

@ -260,3 +260,45 @@ func TrimSpace(s []byte) []byte {
}
return s[start:end];
}
// How big to make a byte array when growing.
// Heuristic: Scale by 50% to give n log n time.
func resize(n int) int {
if n < 16 {
n = 16
}
return n + n/2;
}
// Add appends the contents of t to the end of s and returns the result.
// If s has enough capacity, it is extended in place; otherwise a
// new array is allocated and returned.
func Add(s, t []byte) []byte {
lens := len(s);
lent := len(t);
if lens + lent <= cap(s) {
s = s[0:lens+lent];
} else {
news := make([]byte, lens+lent, resize(lens+lent));
Copy(news, s);
s = news;
}
Copy(s[lens:lens+lent], t);
return s;
}
// AddByte appends byte b to the end of s and returns the result.
// If s has enough capacity, it is extended in place; otherwise a
// new array is allocated and returned.
func AddByte(s []byte, t byte) []byte {
lens := len(s);
if lens + 1 <= cap(s) {
s = s[0:lens+1];
} else {
news := make([]byte, lens+1, resize(lens+1));
Copy(news, s);
s = news;
}
s[lens] = t;
return s;
}